 The first scientific description of the plain maskray was authored by Commonwealth Scientific and Industrial Research Organisation ( CSIRO ) researcher Peter Last in a 1987 issue of Memoirs of the National Museum of Victoria . The specific name annotatus comes from the Latin an (  not  ) and notatus (  marked ) , and refers to the ray 's coloration . The holotype is a male 21 @.@ 2 cm ( 8 @.@ 3 in ) across , caught off Western Australia ; several paratypes were also designated . Last tentatively placed the species in the genus Dasyatis , noting that it belonged to the  maskray  species group that also included the bluespotted stingray ( then Dasyatis kuhlii ) . In 2008 , Last and William White elevated the kuhlii group to the rank of full genus as Neotrygon , on the basis of morphological and molecular phylogenetic evidence . In a 2012 phylogenetic analysis based on mitochondrial and nuclear DNA , the plain maskray and the Ningaloo maskray ( N. ningalooensis ) were found to be the most basal members of Neotrygon . The divergence of the N. annotata lineage was estimated to have occurred ~ 54 Ma . Furthermore , the individuals sequenced in the study sorted into two genetically distinct clades , suggesting that N. annotata is a cryptic species complex . The two putative species were estimated to have diverged ~ 4 @.@ 9 Ma ; the precipitating event was likely the splitting of the ancestral population by coastline changes . fill in the blank  :  The first scientific description of the plain maskray was authored by Commonwealth Scientific and Industrial Research Organisation ( __________________ ) researcher Peter Last in a 1987 issue of Memoirs of the National Museum of Victoria . 